Question

How to find the standard form of the equation of the specified circle given Center: (0,0); Radius: 9?

Answer 1

`x^2+y^2=81`

Explanation:

The standard form for the equation of a circle with center `(color(red)a,color(blue)b)` and radius `color(magenta)r` is
`color(white)("XXX")(x-color(red)a)^2+(y-color(blue)b)^2=color(magenta)r^2`

Answer 2

`x^2+y^2=81`

Explanation:

`"the standard form of the equation of a circle is"`

`color(red)(bar(ul(|color(white)(2/2)color(black)((x-a)^2+(y-b)^2=r^2)color(white)(2/2)|)))`

`"where "(a,b)" are the coordinates of the centre and r is"`
`"the radius"`

`"here "(a,b)=(0,0)" and "r=9`

`rArr(x-0)^2+(y-0)^2=9^2`

`rArrx^2+y^2=81larrcolor(red)"in standard form"`